Why People Aggress

Human aggression is among the greatest dangers to the welfare if not the very survival of our species. Each year, millions of people around the globe are victims of interpersonal aggression, in the form of domestic violence, robberies, rape, and homicide.  What is it about human psychology that allows aggression to spin out of control, like a hurricane destroying everything in its path?

A famous early hypothesis tied aggression to frustration, the thwarting of one's progress toward one's goals. It suggested that people aggress only when frustrated, and any act of aggression is a consequence of some frustration. This strong version of the hypothesis was quickly abandoned as scholars realized that frustration does not inevitably lead to aggression, though they continued to maintain that any aggression is in response to frustration. In this version of the hypothesis, frustration was seen as a necessary, though not a sufficient condition for aggression.

Our work on the frustration-aggression connection asked a basic question: why should frustration lead to aggression in the first place? What function does aggression serve that makes it a fitting response to frustration? The answer to this question not only illuminates the frustration-aggression connection; it also casts light on the psychological essence of human aggression. 

In reviewing past studies that manipulated frustration and observed whether aggression occurs in response, my colleagues and I noted something curious. Typically, the 'frustration' involved subjecting research participants to insults, humiliation, and put-downs. These circumstances indeed elicit an aggressive response. Interestingly, however, when the induced frustration did not entail humiliation (e.g. a bus doesn't stop for you at the bus stop but you see that it is "out of service"), no aggressive response occurred.

This observation suggested an intriguing possibility: that frustration is understood as significance loss, by which we mean a reduction in one's sense of social worth, dignity, and mattering. In other words, frustration as such may not elicit aggression—only frustration of one's need for significance.

That realization solved another puzzle that had mystified us: Why should frustration elicit aggression in the first place as opposed to, say, withdrawal, escape, sulking, etc.? Aggression is a primordial way of asserting one's power, dominance, and hence significance. This notion is shared by evolutionary psychologists and lay observers alike. Chairman Mao Zedong famously proclaimed that "Power grows out of the barrel of a gun." Jean-Paul Sartre, in his preface to Franz Fanon's anti-colonialist classic "The Wretched of the Earth," stated that "irrepressible violence …is man recreating himself" and that it is through "mad fury" that the "wretched of the earth" can "become men."

The view that it is significance loss that elicits aggression is consistent with the large body of research on the frustration-aggression hypothesis as well as supported by new research conducted by our team.

One of our studies involved 272 "incels," members of an online community of young men who consider themselves unable to attract women sexually, and are known to be hostile and verbally aggressive toward women and toward sexually active men.  We found a positive association between participants' significance loss and their willingness to commit rape, moderated by participants' expressed admiration for Elliot Rodger, who in a fit of misogynous rage killed six people in Isla Vista, California. In other words, significance loss predicts hostility toward women.

In another study, we conducted an automated text analysis of Yelp reviews of coffee shops in Austin, Texas, and of U.S. hotels. Within both data sets, terms like "humiliation", "shame" or "insult" related to significance loss people experienced at the evaluated establishments were negatively related to the number of Yelp review stars they assigned to a given coffee shop or hotel.

These and other studies support the idea that aggression is an evolved response to significance loss, a primitive way to restore a sense of significance. This notion has an important implication, namely that aggression isn't a fundamental need as Freud and other instinct theorists have surmised, but rather a means to the attainment of significance that can be substituted by other, prosocial means to the same end.  If so, there is room for hope that cultivating the latter means, as well as creating a just society where people feel significant and respected, will ultimately conquer the monster of human aggressiveness. 

Further Readings

Kruglanski, A.W., Ellenberg, M., Szumowska, E., Molinario, E. Speckhard, A., Leander, N.P., Pierro, A. Di Cicco, G. & Bushman, B. (2023). Frustration-Aggression hypothesis reconsidered: The role of significance quest. Aggressive Behavior, 49, 445-468.  https://doi.org/10.1002/ab.22092

Kruglanski, A.W., Molinario, E., Jasko, K. Webber, D., Leander, N.P. & Pierro, A. (2022). Significance Quest Theory. Perspectives in Psychological Science, 49, (17), 1-22.  https://doi.org/10.1177/17456916211034825
 

Arie Kruglanski is a Distinguished University Professor in the Department of Psychology at the University of Maryland, College Park.  He has served as editor of several scientific journals and as President of the Society for the Study of Motivation. He studies human judgment and decision-making, the interface between motivation and cognition, group and intergroup processes, the psychology of human goals, and the social psychological aspects of terrorism.